Text Tools · Group 02 of 09
Seven one-click transforms for reshaping the case of any text — UPPER, lower, Title, Sentence and three flavours of mixed case. Pick a style and watch every conversion update live, right in your tab. Nothing is uploaded, nothing is stored.
The Uppercase Converter turns every letter into capitals in one click. It's the fastest way to produce shouting headlines, warning labels, acronym-ready copy or emphasis that simply cannot be missed — without holding the shift key or fighting your keyboard.
"hello WORLD, how are you?"
"HELLO WORLD, HOW ARE YOU?" — digits and punctuation pass through unchanged.
Use it for headlines & bannerswarning labelsacronyms & codesstrong emphasis
The Lowercase Converter folds every capital letter down to small case. It's the standard fix for text pasted from PDFs, slides or ALL-CAPS emails, and the right first step before building URL slugs, comparing strings or normalising data for a spreadsheet.
"Hello WORLD, How Are You?"
"hello world, how are you?" — one click, every capital gone.
Use it for cleaning ALL-CAPS textURL slugsnormalising dataemail etiquette
The Title Case Converter capitalises the first letter of every word and lowercases the rest — the standard treatment for headlines, book titles and navigation labels. Unlike Capitalize Words, it also fixes stray capitals hiding in the middle of words.
"the QUICK brown fox jumps"
"The Quick Brown Fox Jumps" — "QUICK" is tamed, not just capped.
Use it for headlines & titlesnav labelsYouTube titlesfile names
The Sentence Case Converter lowercases everything, then capitalises only the first letter of each sentence — the style preferred by most modern style guides for body copy. It finds sentence boundaries by their terminal punctuation (. ! ? …) and the start of new lines.
"hello WORLD. how ARE you? fine!"
"Hello world. How are you? Fine!" — one capital per sentence, nothing more.
Use it for body copystyle-guide cleanupessays & reportsUI text
Toggle Case flips the case of every single letter: uppercase becomes lowercase and lowercase becomes uppercase, character by character. Numbers, spaces and punctuation pass through untouched. It's the classic sWaP-cAsE operation programmers know as swapcase.
"Hello World 2026"
"hELLO wORLD 2026" — each letter swapped, digits kept.
Use it for case repairobfuscationstylistic effectstesting & QA
Capitalize Words uppercases only the first letter of each word and leaves every other character exactly as you wrote it. Use it when the original casing carries meaning — product names, part numbers, codes — and a full Title Case conversion would destroy information.
"hello WORLD product X9"
"Hello WORLD Product X9" — "WORLD" and "X9" keep their casing.
Use it for product namespart numbersnames & listsgentle capitalisation
The Invert Case converter rewrites your text in alternating case, starting with a lowercase letter: hElLo wOrLd. Only letters count toward the alternation — spaces, digits and punctuation are skipped without breaking the rhythm. A favourite for memes, usernames and deliberately chaotic styling.
"Hello World"
"hElLo wOrLd" — alternating letter by letter, spaces skipped.
Use it for memes & jokesusernamesDiscord / Steam namesvisual noise
Conversion rules · title = first letter up, rest down · capitalize = first letter up, rest untouched · sentence = capital after . ! ? … and new lines · toggle = swap every letter · invert = alternate, starting lowercase · non-letters never change
This page has no backend and no database. Every conversion you just watched was computed by JavaScript inside your own browser tab — your text never traveled a single centimeter of cable. Close the page and it's gone for good.
Title Case lowercases the rest of every word as it capitalizes the first letter — "the QUICK fox" becomes "The Quick Fox". Capitalize Words only touches the first letter of each word and leaves everything else exactly as you typed it — "the QUICK fox" becomes "The QUICK Fox". Use Title Case for headlines; use Capitalize Words when the original casing carries meaning.
Toggle Case swaps the case of every letter, one by one: "Hello" becomes "hELLO". Invert Case rewrites the text in alternating case starting with a lowercase letter: "Hello World" becomes "hElLo wOrLd". In both tools, spaces, digits and punctuation are never altered — and in Invert Case they don't count toward the alternation.
No — no case converter can tell that "paris" is a name. It lowercases everything, then capitalizes the first letter after each sentence boundary (. ! ? … and new lines). Run it first, then re-capitalize names, brands and acronyms by hand.
No. IrisTool has no backend and no database. All conversion runs inside your browser tab and disappears the moment you close or refresh the page. There is nothing to leak, because nothing is ever collected.
Yes. Once the page has loaded, every tool on it keeps working offline, because all the logic runs locally in your browser.